[Importance and trends of prenatal diagnostics].

The prenatal diagnosis in the middle third of a pregnancy serves the purpose to avoid the birth of children with genetic defects. Its most important indications are: Age of the mother more than 38 years, previous birth of a child with chromosomal anomaly, birth of a child with defect of the neural tube or with biochemically diagnosable metabolic disease and the diagnosis of sex in X-chromosomal hereditary diseases. The amniocentesis necessary for this is performed in the 16th week of pregnancy. In cytogenetic problems the result is present, as a rule, within the following 2-3 weeks, whereas the biochemical diagnosis lasts somewhat longer depending on the growth of the cells. The task of the following years will be to shorten the times of diagnosis and to increase the number of prenatally recognizable genetic and genetically conditioned diseases, respectively.